background preloader

Logic Puzzles - Solve Online or Print Your Own for Free!

Logic Puzzles - Solve Online or Print Your Own for Free!
Related:  games

Printable Puzzles ZTOR Logical games. On-line World Championship Cryptograms.org - Home Relational Logic: Satisfaction and Logical Entailment We observed that a lot of the students are struggling with Problem 6.5. Therefore, we've provided the following exercise that presents four different variants of the Problem 6.5 along with hints regarding the satisfiability and entailment of the supplied relational logic sentences. Our hope is that after trying out and / or seeing the answers of this exercise, the students can better understand the relationship and the differences between consistency (also called satisfiable) and logical entailment of sentences. You can access the four variants of Problem 6.5 by choosing the appropriate option from the following dropdown menu. By default, Variant 1 is loaded. Let's suppose that our vocabulary consists of the object constants: a, b and c and the binary relation constants p and r. Consider the following sentence about r. r(a, b) ∧ r(b, c) Say whether each of the following sentences is (a) consistent with the above sentence about r, and (b) logically entailed by the above sentence about r. 1.

Pfadi Lachen - Logical Lust auf ein, zwei knackige Rätsel? Auf dieser Seite findest du sogenannte Logical, welche du ausdrucken und lösen kannst. Viel Spass dabei. Wie löse ich ein Logical? Ein Logical zu lösen ist eigentlich gar nicht so schwer. Wie's genau funktioniert (PDF-Datei, 96 kb) Immer diese Unfälle Diese Leiter! Und los geht's (PDF-Datei, 148 kb) Die Anleitung, wie man ein Logical löst, findest du oben. Die Taufe Vier junge Pfadi aus verschiedenen Ortschaften sind zum ersten Mal im Pfi nstlager. Und los geht's (PDF-Datei, 206 kb) Tag der offenen Archivtüre Beim Tag der offenen Archivtüre im letzten Jahr war der Andrang so gross, dass Mädli und Komet mit Beschriften der Kisten nicht mehr nachkamen. Und los geht's (PDF-Datei, 81 kb) Pfadilager Finde heraus, wie die Zelte auf dem Pfadilagerplatz verteilt sind. Die Zahlen am linken und oberen Rand geben an, wieviele Zelte in der jeweiligen Zeile bzw. Zeichne die Zelte ein - (PDF-Datei, 204 kb), inkl. Nach einer Idee von janko.at Missgeschicke

Pastel Games Building Models Introduction to Logic 1. Introduction In Relational Logic, it is possible to analyze the properties of sentences in much the same way as in Propositional logic. The main problem in doing this sort of analysis for relational logic is that the number of possibilities is even larger than in propositional logic. Fortunately, as with Propositional Logic, there are some shortcuts that allow us to analyze sentences in relational logic without examining all of these possibilities. 2. In the Boolean model approach, we write out an empty table for each relation and then fill in values based on the constraints of the problem. As an example, consider the Sorority problem introduced in Chapter 1. In this particular case, it turns out that there is just one model that satisfies all of these sentences. The data we are given has three units - the fact that Dana likes Cody and the facts that Abby does not like Dana and Dana does not like Abby. Now, we know that Abby likes everyone that Bess likes. 3.

Logical - Rätsel-Forum - Logikrätsel Ein Logical, auf deutsch Logikrätsel, ist ein Rätsel, das nur durch logische Schlussfolgerungen lösbar ist. Das bekannteste dürfte wohl das Einstein-Rätsel sein, das auch unter dem Namen Zebrarätsel bekannt ist. Angeblich soll Albert Einstein dazu gesagt haben, dass nur 2 % der Bevölkerung in der Lage wären, dieses Rätsel zu lösen. Wenn Sie glauben die Lösung gefunden zu haben, geben Sie sie in unser Lösungsformular ein und Sie erfahren sofort, ob Sie zu den wenigen Menschen gehören, die ein Logical lösen können. Wenn Sie bisher noch kein Logikrätsel gelöst haben, sollten Sie am besten mit dem Nikolaus-Logical beginnen. Dieses hat nur wenige Felder und es werden viele Tipps gegeben. Im Rätsel-Forum werden fleißig Rätsel erstellt und gelöst. Tipps 1. 2. 3. 4. 5. 6. 7. 8. 9. Finden Sie heraus, wer welches Rätsel wann erstellt hat und von wem es in welcher Zeit gelöst wurde.

Be-Fitched! Constructing proofs using the Fitch system can often be hard and unintuitive, especially for those who encounter it for the first time. We have identified the following guidelines which are based on the properties of the Goal or of the Premises that could potentially help you with Fitch-style proofs. Guidelines based on propeties of the Goal: Goal is of the form φ ⇒ ψ Assume φ Prove ψ Apply Implication Introduction to prove φ ⇒ ψ Goal is of the form ¬φ Assume φ Find a sentence ψ Prove φ ⇒ ψ Prove φ ⇒ ¬ψ Apply Negation Introduction to prove ¬φ The idea behind G2 is to assume φ and show that this leads to a contradiction i.e. ψ and ¬ψ. Good candidates for ψ when applying Negation Introduction on φ ⇒ ψ and φ ⇒ ¬ψ are the premises or the assumptions (for the sub-proof). Consider the following example. Guidelines based on propeties of Premises: Comprehensive example Apply G1-G5 to reverse-engineer which sub-goals to prove prior to proving the goal.

Mendelson Proof Tips Contradiction Realization (CR): (¬φ ⇒ ψ) ⇒ ((¬φ ⇒ ¬ψ) ⇒ φ) Observation: CR = application of Negation Introduction to prove ¬¬φ followed by Negation Elimination to prove φ. Good idea to use CR when the goal contains no implications, or if the premises have negations. (For e.g. consider Problem 4.1). For example in problem 4.2, we have to prove p from the premise ¬¬p. Note that in the Fitch system, one would start by assuming ¬p;, re-iterate ¬¬p, and finally apply Implication Introduction.

Combinational Circuit Diagnosis Once again, consider the Combinational Circuit Verification example. The focus there is on a full adder, i.e. a combinational circuit with the schematic diagram shown below. The example shows how to model this circuit in the form of logical sentences that describe the behavior of the individual gates. Of course, this description assumes that all of the components are behaving correctly. One advantage of doing things this way is that we can use logical deduction to diagnosis hardware failures. Using this data together with the sentences above and using logical deduction, we can derive the following conclusions. the first conclusion below comes from the erroneous sum bit, and the second comes from the erroneous carry bit. A common assumption in hardware diagnosis is that at most one component is failing.

Combinational Circuit Verification A combinational circuit is a collection of interconnected digital components called gates. Gates have inputs and outputs. When Boolean signals (1 or 0) are applied to the inputs of a gate, the circuit produces a corresponding output depending on the type of the gate. The following illustration is a schematic diagram for a combinational circuit called a full adder. The purpose of a full-adder is to do one slice of binary addition. We can encode the behavior of the individual gates in a circuit like this using the language of Propositional Logic. As mentioned above, the purpose of a full adder is to compute one slice of binary addition. Once we have expressed things in this way, we can use the tools of Propositional Logic to verify that the circuit works correctly.

Whodunnit Victor has been murdered, and Art, Bob, and Carl are suspects. Art says he did not do it. He says that Bob was the victim's friend but that Carl hated the victim. Bob says he was out of town the day of the murder, and besides he didn't even know the guy. Carl says he is innocent and he saw Art and Bob with the victim just before the murder. Assuming that everyone - except possibly for the murderer - is telling the truth, encode the facts of the case so that you can use the tools of Propositional Logic to convince people that Bob killed Victor. The key to using Logic to solve this problem is to make the suspects' statements conditional on their innocence. Given this vocabulary, we can encode the facts of the case as shown below. In addition, we can encode some general facts as shown below. Finally, we make the assumption that there is only one guilty party. Once we have formalized the problem in this way, we can use the tools of Propositional Logic to prove Bob's guilt.

Related: